Shortening boat propeller shafts

I am making a scratch built balsa hull boat from the plans of the full sized craft which necessitates a very short propellor shaft. As these are not available I am seeking advice on the feasibility of purchasing a standard shaft, removing one of the bushes and shortening the tube before replacing the bush. 
Has anybody done this if so any advice would be very helpful.

No problem, I do it all the time. 
Just make sure you the cut end is square and remove ALL the metal debris before you refit the bearing. Also if it is a little loose then a drop of superglue or solder to make sure it doesn't drop out.


Mike